JP2003200319A - Electric discharge machining device and electric discharge machining method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric discharge machining device easily positioning an electrode for a member to be machined. <P>SOLUTION: A conical recessed surface 11 reduced in diameter toward a machined hole 12 formed by electric discharge machining is formed in a body 10. A conical projecting surface 24 having the same inclined angle as that of the conical recessed surface 11 is formed at a side end part of the conical recessed surface 11 of an electrode guide 20 for guiding the electrode 30 toward the machined hole 12. By abutting the conical recessed surface 11 and the conical projecting surface 24 and pushing the electrode guide 20 toward the conical recessed surface 11, the centers of the conical recessed surface 11 and the conical projecting surface 24 can be easily aligned. By rotating the electrode guide 20 during electric discharge machining, the center of the machined hole 12 formed by electric discharge machining substantially coincides with the center of the conical recessed surface 11. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric discharge machine for forming a machined hole in a member to be machined.

[0002]

2. Description of the Related Art There is known an electric discharge machining apparatus for forming a machining hole in a workpiece by applying a high voltage between an electrode and the workpiece to cause electrical discharge. In order to process a workpiece with high precision using an electric discharge machine, it is necessary to prevent the electrode from swinging during electric discharge machining. In order to prevent the electrode from swinging during electric discharge machining, a configuration is known in which a guide member guides the electrode near the workpiece. The electric discharge machining apparatus disclosed in Japanese Patent Laid-Open No. 6-91436 prevents a deflection of the electrode during electric discharge machining by abutting a guide member that guides the electrode against the member to be machined. I'm trying to process it.

[0003]

In order to machine a member to be machined with high accuracy, it is possible to prevent deflection of the electrode during electric discharge machining and to position the electrode, that is, the guide member, with respect to the member to be machined with high accuracy. There must be. However, it is difficult to position the guide member on the member to be processed with high accuracy only by bringing the guide member into contact with the member to be processed. Further, even if the guide member can be positioned with high precision with respect to the workpiece, if the guide member has a manufacturing error, the electrode cannot be accurately positioned with respect to the workpiece.

It is an object of the present invention to provide an electric discharge machine which facilitates positioning of electrodes with respect to a member to be machined. Another object of the present invention is to provide an electrical discharge machining apparatus and an electrical discharge machining method for machining a workpiece with high accuracy even if the guide member has a manufacturing error.

[0005]

According to the electric discharge machining apparatus of the first aspect of the present invention, a conical concave surface whose diameter is reduced toward the machining hole for electric discharge machining is formed on the member to be machined and abuts against the conical concave surface. As a result, an inclined surface centered on the conical concave surface is formed at the end of the guide member on the side of the processed hole. When the inclined surface of the guide member is brought into contact with the conical concave surface of the member to be processed and the guide member is pushed toward the processing hole side, the inclined surface is guided by the conical concave surface and the guide member is positioned with respect to the member to be processed. The centers of the conical concave surface of the processing member and the inclined surface of the guide member can be aligned. Since the guide member can be easily and accurately positioned with respect to the member to be processed, the electrode can be accurately positioned with respect to the member to be processed, and the processed hole can be formed with high accuracy.

According to the electric discharge machining apparatus of the second aspect of the present invention, the conical concave surface and the conical convex surface are in surface contact by making the inclined surface formed on the guide member a conical convex surface having the same inclination angle as the workpiece. However, the position of the conical convex surface is unlikely to shift from the conical concave surface. Therefore, the center of the conical concave surface of the member to be processed and the center of the conical convex surface of the guide member can be reliably aligned. Furthermore, since the conical concave surface of the workpiece and the conical convex surface of the guide member are in surface contact with each other, the guide member having the conical convex surface is unlikely to tilt. Since the electrode guided by the guide member is also unlikely to tilt, it is possible to prevent deformation of the processed hole. Further, it is easy to form the conical convex surface on the guide member.

Even if the conical concave surface of the member to be machined and the inclined surface of the guide member are brought into contact with each other to center the conical concave surface and the inclined surface, for example, a through hole of the guide member accommodating the electrode so as to be reciprocally movable. When the centers of the inclined surface and the inclined surface are deviated, the centers of the through hole and the conical concave surface are deviated. Then, the center of the machining hole to be electric discharge machined by the electrode housed in the through hole is displaced from the center of the conical concave surface. According to the electric discharge machining apparatus according to claim 3 or the electric discharge machining method according to claim 6 or 8 of the present invention, by rotating the guide member during electric discharge machining, for example, the penetration of the guide member that accommodates the electrode in a reciprocating manner is possible. When the center of the hole and the inclined surface are deviated, the through hole of the guide member revolves around the center of the conical concave surface of the workpiece and the inclined surface of the guide member. Since the electrode housed in the through hole of the guide member also revolves around the center of the conical concave surface of the workpiece and the inclined surface of the guide member, the center of the machining hole formed by electrical discharge machining is the conical concave surface of the workpiece. Almost coincides with the center of. According to the electrical discharge machining apparatus according to claim 4 or the electrical discharge machining method according to claim 7 or 8, the electrode is rotated during the electrical discharge machining, so that the electrode has a circular cross-section even if there is a manufacturing error in the electrode. Holes can be formed with high precision.

When the guide member and the electrode are rotated in the same direction, the rotation speeds of the guide member and the electrode may be the same. As described above, when the through hole of the guide member and the inclined surface are displaced from each other and the electrode revolves around the center of the inclined surface of the guide member, the guide member and the electrode rotate in the same direction and the guide member and the electrode. When the rotation speeds of and are the same, a specific portion of the outer peripheral side surface of the electrode always faces radially outward and faces the inner peripheral side surface of the processed hole. Since the discharge is generated at a small discharge gap, a specific portion of the electrode facing the inner peripheral side surface of the processed hole is discharged with the inner peripheral side surface of the processed hole, and the specific portion of the electrode is consumed. When the specific portion of the electrode is consumed, the discharge gap between the specific portion of the electrode and the processed hole becomes large, so that the processed hole is deformed and the diameter of the processed hole becomes small.

In order to solve this problem, claim 5 of the present invention
According to the electric discharge machining apparatus described above or the electric discharge machining method according to claim 9, the electrode is rotated in a direction opposite to the rotation direction of the guide member. When the through hole of the guide member and the inclined surface are displaced from each other, and when the electrode revolves around the center of the inclined surface of the guide member, different points in the circumferential direction of the outer peripheral side surface of the electrode are sequentially the inner peripheral side surface of the machined hole. Face with. Since different portions in the circumferential direction of the outer peripheral side surface of the electrode are sequentially discharged with the inner peripheral side surface of the machined hole, it is possible to prevent the specific part of the electrode from being consumed and prevent the machining hole from being deformed.

Further, the relative rotation speed of the electrode with respect to the guide member is the sum of the speeds because the electrodes rotate in opposite directions. Even if the rotation speed of the guide member is slowed, the electrode can obtain a desired relative rotation speed with respect to the guide member, so that wear of the inclined surface of the guide member that slides on the conical concave surface of the workpiece can be reduced.

When the electrode revolves by the rotation of the guide member, that is, when the inner peripheral side surface of the machining hole located at the revolving destination faces the electrode, the workpiece to be removed by electric discharge machining per unit time When the removal amount, that is, the revolution speed of the electrode is faster than the machining speed, the electrode comes into contact with the member to be processed, and no electric discharge occurs between the member to be processed and the electrode. According to the electric discharge machining method of the tenth aspect of the present invention, while rotating the guide member, the rotation speed of the guide member is feedback-controlled while detecting the discharge voltage generated between the workpiece and the electrode. For example, when the discharge voltage generated between the member to be processed and the electrode becomes 0, the rotation speed of the guide member is too fast and the electrode may be in contact with the member to be processed, so that the rotation speed of the guide member is reduced. . In this way, the rotation speed of the guide member can be adjusted so as to optimize the gap formed in the rotation direction between the electrode and the member to be processed.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows an electric discharge machine according to an embodiment of the present invention. A workpiece 10 as a member to be processed is, for example, a body before injection hole formation of an injector, and is immersed in a machining liquid during electric discharge machining. As the processing liquid, for example, water or oil is used. The work 10 is formed with a conical concave surface 11 whose diameter is reduced toward a machining hole 12 formed by electric discharge machining. The electrode guide 20 as a guide member is housed in the housing hole 14 of the work 10.
The electrode guide 20 accommodates an elongated cylindrical electrode 30 so as to be capable of reciprocating, and has a through hole 20 a for guiding the electrode toward the processed hole 12. The electrode guide 20 receives torque from a motor 50 as an electrode rotating means and rotates.

The electrode guide 20 connects a gear 21 that receives torque from the motor 50, insulating portions 22 and 23 that come into contact with the inner peripheral wall of the work 10, and a small-diameter guiding portion that connects both insulating portions axially separated from each other. 25 and. Conical concave surface 11
The insulating portion 23 located on the side has a conical convex surface 24 as an inclined surface that contacts the conical concave surface 11. The inclination angle of the conical convex surface 24 is the same as that of the conical concave surface 11.

A machining liquid channel 22a is formed on the outer peripheral wall of the insulating portion 22, and machining liquid channels 23a, 24a are formed on the outer peripheral wall of the insulating portion 23 including the conical convex surface 24. The machining fluid channels 22a, 23a, and 24a are used for the insulating portion 2 during the electric discharge machining.
The working liquid is formed so as to flow to the tip end 31 side of the electrode 30 in a state where the inner surfaces of the workpieces 2 and 23 are in contact with each other. The electrode 30 has an elongated cylindrical shape and has a plate-shaped connecting portion 32 at the diameter position.

The discharge head 40 applies a discharge voltage to the electrode 30 and fixes and rotates the electrode 30. The discharge head 40 has a rotation driving unit 41 as a guide member rotating unit and a chuck 42 for fixing the electrode 30. The chuck 42 receives a driving force from the rotation driving unit 41 and rotates together with the electrode 30. In the discharge head 40,
A working liquid suction pipe 43 for sucking the working liquid in the electrode 30 is connected.

Next, the electric discharge machining method will be described. (1) As shown in FIG. 2, the electrode guide 20 is inserted into the work 10 while the electrode 30 is not inserted into the electrode guide 20. Since the conical convex surface 24 of the insulating portion 23 and the conical concave surface 11 of the work 10 have the same inclination angle, the conical concave surface 11
By pushing the electrode guide 20 toward the conical concave surface 11 while bringing the conical convex surface 24 into contact with the workpiece 10, the electrode guide 20 is positioned with respect to the workpiece 10 and the centers of the conical concave surface 11 and the conical convex surface 24 can be easily aligned. it can. Further, since the conical concave surface 11 and the conical convex surface 24 have the same inclination angle, when the centers of the conical concave surface 11 and the conical convex surface 24 are aligned, the conical concave surface 11 and the conical convex surface 24 are in surface contact with each other. Since the position of the conical convex surface 24 is unlikely to shift with respect to the conical concave surface 11, the electrode guide 20 having the conical convex surface 24 is unlikely to tilt.

(2) With the conical concave surface 11 and the conical convex surface 24 aligned with each other, the electrode 30 is inserted into the electrode guide 20 and fixed by the chuck 42. As mentioned above, the electrode guide 2
Since 0 is hard to tilt, the electrode 30 housed in the electrode guide 20 is also hard to tilt. (3) During the electric discharge machining, the electrode 30 passes through the machining fluid flow path 22a, the accommodation hole 14, and the machining fluid flow paths 23a and 24a as shown in FIG.
The working liquid supplied to the tip 31 side of the is passed through the electrode 30 and is sucked by the working liquid suction pipe 43. At this time, as shown in FIG. 3, machining scraps 200 generated by electric discharge machining
Passes through the electrode 30 together with the working fluid and the working fluid suction pipe 43.
Is aspirated by.

During the electric discharge machining, the electrode guide 20 and the electrode 3
0 and 0 are rotated in opposite directions as shown in FIG. As shown in FIG. 4A, when the center of the through hole 20a of the electrode guide 20 and the center of the conical convex surface 24 deviate, the center of the electrode 30 and the conical concave surface 11 accommodated in the through hole 20a deviate. ing. In this state, when the electrode guide 20 is rotated during electric discharge machining as shown in FIG. 4A, the tip 31 of the electrode 30 revolves on the circle 112 as shown in FIG. 4B.
The amount of deviation between the center of the through hole 20a and the center of the conical convex surface 24,
That is, as shown in FIG. 5, the center 11 of the tip 31 of the electrode 30 is
If the amount of deviation between 0 and the center 100 of the conical concave surface 11 is d, the diameter of the circle 112 shown in FIG. 4B is 2d.
The inner diameter of the processed hole 12 is substantially equal to the diameter of the tip 31 plus 2d. Therefore, the center 120 of the machined hole 12 formed by the tip 31 of the electrode 30 has a conical concave surface 11
It almost coincides with the center 100 of.

The center of the through hole 20a of the electrode guide 20 and the center of the conical convex surface 24 are displaced, and the through hole 2 of the electrode guide 20 is formed.
When the electrode 30 housed in the electrode 0a revolves around the center of the conical convex surface 24 of the electrode guide 20, the outer peripheral side surface 31a of the tip 31 of the electrode 30 is arranged so that different portions in the circumferential direction become the inner peripheral side surface of the machined hole 12 sequentially. The inner peripheral side surface of the facing processed hole 12 is discharged. By rotating the electrode guide 20 and the electrode 30 in opposite directions, it is possible to prevent a specific portion of the electrode 30 from being consumed and prevent the machining hole 12 from being deformed.

Further, the relative rotation speed of the electrode 30 with respect to the electrode guide 20 is the sum of the respective rotation speeds because they rotate in opposite directions. Even if the rotation speed of the electrode guide 20 is slowed down, the electrode 30 can obtain a desired relative rotation speed with respect to the electrode guide 20, so that the conical concave surface 24 of the electrode guide 20 sliding with the conical concave surface 11 of the workpiece 10 can be obtained.
Wear can be reduced.

During the electric discharge machining, the average value of the electric discharge voltage applied between the electrode 30 and the work 10 is detected, and the electric discharge head 4 is detected.
The rotation speed of 0 and the moving amount of the discharge head 40 in the downward direction in FIG. 1, that is, the feeding amount of the electrode 30 are adjusted. Electrode 3
When 0 contacts the work 10, the discharge voltage becomes 0, so
When the average value of the discharge voltage drops below a predetermined value, the electrode 30
Is in contact with the work 10. If the feed rate of the electrode 30 in the axial direction is too fast, the tip 31 of the electrode 30 contacts the bottom of the processed hole 12. Further, if the rotation speed of the electrode guide 20 that revolves the electrode 30 is too fast, as shown in FIG. Come into contact with.
However, it is not possible to distinguish whether the electrode 30 is in contact with the work 10 due to the feed speed of the electrode 30 or the rotation speed of the electrode guide 20 only by lowering the average voltage.

Therefore, the feeding of the electrode 30 and the rotation of the electrode guide 20 are stopped, the electrode 30 is slightly returned in the direction opposite to the feeding direction, and the electrode guide 20 is slightly returned in the opposite rotational direction. As a result, the processed hole 12 and the electrode 30 are separated from each other. Then, the feed speed of the electrode 30 and the electrode guide 2
The rotation speed of 0 is reduced from that before the stop, and the rotation of the electrode guide 20 and the feeding of the electrode 30 are restarted. (4) When the discharge head 40 moves downward in FIG. 1 by a predetermined amount,
It is determined that the processing of the processed hole 12 is completed. After forming the processed hole 12, the injection hole 16 is further formed by electric discharge machining or the like.

As in this embodiment, it is easy to machine the conical concave surface 11 and the conical convex surface 24 to have the same inclination angle in order to align the centers of the conical concave surface 11 and the conical convex surface 24. However, as described above, the center between the through hole 20a of the electrode guide 20 into which the electrode 30 is inserted and the conical convex surface 24 may be slightly displaced during manufacturing, as described above. Even if the centers of the conical concave surface 11 and the conical convex surface 24 coincide with each other, if the electric discharge machining is performed without rotating the electrode guide 20 with the axial center of the through hole 20a deviating from the center of the conical convex surface 24, the electrode 30 The center of the machining hole 12 to be electric discharge machined by is displaced from the center of the conical concave surface 11. Through hole 20a due to manufacturing error
The amount by which the axis center of is displaced from the center of the conical convex surface 24 is small.

However, as shown in FIG. 6, for example, a machining chamber 12 formed by electric discharge machining forms a fuel chamber 70, and the tip 64 of the nozzle needle 60 is formed in the fuel chamber 70.
In the injector in which the through hole 20a
When the center of the machining hole 12 that is subjected to electric discharge machining deviates from the center of the conical concave surface 11 by shifting the axial center of the machining center from the center of the conical convex surface 24, the injection hole 16 formed after the machining hole 12 is formed.
It is not possible to control the fuel injection amount injected from the engine with high accuracy. This is because when the center of the processed hole 12 is displaced from the center of the conical concave surface 11, that is, the center of the tip portion 64, the nozzle needle 60
When the abutting portion 62 of is separated from the conical concave surface 11, the passage area formed between the outer peripheral side surface of the tip portion 64 and the inlet of the injection hole 16 varies, and the injection amount from the injection hole 16 varies. is there.

Therefore, in this embodiment, as shown in FIG.
By rotating the electrode guide 20 during electric discharge machining, the tip 31 of the electrode 30 revolves on the circle 112. Therefore, the center 120 of the machined hole 12 formed by the tip 31 of the electrode 30 substantially coincides with the center 100 of the conical concave surface 11. Compared with the conventional electric discharge machining in which the electrode 30 is guided by an electrode guide that does not have a positioning means such as the conical convex surface 24 of the present embodiment that performs centering with the conical concave surface 11 of the workpiece 10.
In this embodiment, as shown in FIG. 7, the deflection of the center of the machined hole 12 with respect to the center of the conical concave surface 11 becomes extremely small. Therefore, in the injector shown in FIG. 6, the center of the conical concave surface 11, that is, the center of the tip portion 64 of the nozzle needle 60 and the center of the processed hole 12 substantially coincide with each other, and the fuel injection amount can be controlled with high accuracy.

However, if the rotating speed of the electrode guide 20 is too fast, the rotating speed of the electrode guide 20 is not equal to the working speed of the electric discharge machining of the machined hole 12, that is, the removal amount of the work 10 removed per unit time by electric discharge. No, electrode 3
0 contacts the work 10. In this embodiment, the electrode 30 is detected by detecting the average voltage of the electric discharge voltage during electric discharge machining.
The gap formed in the rotational direction between the workpiece 10 and the workpiece 10 is optimally maintained so that the electrode 30 does not contact the workpiece 10.
The rotation speed of the electrode guide 20 is adjusted.

Further, in this embodiment, since the inclination angle of the conical concave surface 11 and the inclination angle of the conical convex surface 24 are the same,
The centers of the conical concave surface 11 and the conical convex surface 24 can be easily aligned. Further, when the centers of the conical concave surface 11 and the conical convex surface 24 are aligned with each other, the conical concave surface 11 and the conical convex surface 24 are in surface contact with each other. 20
Is hard to tilt. Therefore, the electrode 30 guided by the electrode guide 20 is also unlikely to be tilted, so that the deformation of the processed hole 12 can be prevented.

Further, in this embodiment, the electrode 30 is used during electric discharge machining.
The machining fluid supplied to the tip end 31 side of the machining fluid suction pipe 43
Is sucked through the electrode 30. As shown in FIG. 3, the machining waste 200 generated by the electric discharge machining is not sucked into the outer peripheral side surface 31 a of the tip 31 of the electrode 30 but is sucked into the electrode 30. The machining waste 200 is not sucked into the electrode 30 and the tip 3
When it moves to the outer peripheral side surface 31 a of No. 1, secondary discharge is generated between the tip 31 and the processed hole 12 via the processing waste 200. Then, the processed hole 12 is further processed, so that the diameter of the processed hole 12 is increased or the processed hole 12 is processed.
The distortion of the shape of reduces the machining accuracy of the machined hole 12. The cutting waste 200 has the tip 31 and the processed hole 12
Since it is sucked into the electrode 30 without moving between and, the processing accuracy of the processed hole 12 is improved.

In this embodiment, the conical concave surface 11 and the conical convex surface 2
4 and the electric discharge machining was performed while rotating the electrode guide 20 to adjust the machining position of the machining hole 12 with high accuracy. However, if the machining accuracy of the through hole 20a that accommodates the electrode 30 is high. The machining hole 12 may be formed without rotating the electrode guide 20 during electric discharge machining.

In this embodiment, the electrode guide 20 and the electrode 30 are rotated in opposite directions so that a specific portion of the electrode 30 is not consumed. On the other hand, the electrode guide 20 and the electrode 30 do not have the same rotation speed, and the specific portion of the electrode 30 is not machined in the hole 1
The electrode guide 20 and the electrode 30 may be rotated in the same direction as long as they do not face the inner peripheral side surface of 2 and discharge electricity from the processed hole 12. Further, in the present embodiment, by rotating the electrode 30, different portions in the circumferential direction of the tip 31 are sequentially processed so that the machined hole 12 is machined in a circular shape even if the cross-sectional shape of the electrode 30 is deformed. It is designed to face the inner side surface and discharge. On the other hand, if the electrode 30 is circularly formed with high precision, the processed hole 12 may be formed without rotating the electrode 30.

In this embodiment, the conical convex surface 24 having the same inclination angle as the conical concave surface 11 of the work 10 is formed on the electrode guide 20, and the conical convex surface 24 contacts the conical concave surface 11 so that the conical concave surface 11 and the conical convex surface 24 are formed. By performing electric discharge machining with the center of the machining center aligned, the runout of the machined hole 12 is reduced. On the other hand, the conical convex surface 24 and the conical concave surface 11 may have different inclination angles. Even with different tilt angles,
Since the electrode guide 20 is guided by the conical concave surface 11, the centers of the conical concave surface 11 and the conical convex surface 24 can be aligned. Further, the tip of the electrode guide may be, for example, a hemispherical convex curved surface.

[Brief description of drawings]

FIG. 1A is a configuration diagram showing an electric discharge machining apparatus according to an embodiment of the present invention, and FIG. 1B is a B direction arrow view without a body.

FIG. 2 is an explanatory view showing the movement of the guide member inserted into the body.

FIG. 3 is an explanatory diagram showing a flow of a working liquid around the tip of an electrode.

FIG. 4A is an explanatory view showing the movement of the guide member and the electrode, and FIG. 4B is an explanatory view showing the conical concave surface of the body and the center of the processed hole.

FIG. 5 is an explanatory diagram showing a displacement of an electrode tip portion with respect to a conical concave surface.

FIG. 6 is a cross-sectional view showing the vicinity of an injection hole of an injector after electric discharge machining.

FIG. 7 is a characteristic diagram showing a deflection rate of a machined hole in this example and a conventional example.

[Explanation of symbols]

10 body (workpiece) 11 Conical concave surface 16 injection holes 20 Electrode guide (guide member) 20a through hole 24 Conical convex surface (slope) 30 electrodes 40 discharge head 41 Rotational drive unit (guide member rotating means) 50 motor (electrode rotating means)

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Fumiyoshi Kano             1-1, Showa-cho, Kariya city, Aichi stock market             Inside the company DENSO F term (reference) 3C059 AA01 AB07 CH08 DD01 DD10

Claims (10)

[Claims] 1. A member to be processed, an electrode for generating an electric discharge between the member to be processed and forming a processing hole in the member to be processed, the electrode being housed so as to be reciprocally movable in an axial direction, A guide member that guides the electrode toward the processing hole, and a conical concave surface whose diameter is reduced toward the processing hole is formed on the member to be processed, and the conical concave surface and the center are formed by contacting the conical concave surface. An electric discharge machining apparatus, wherein an inclined surface to be fitted is formed at an end portion of the guide member on the machining hole side. 2. The electric discharge machine according to claim 1, wherein the inclined surface is a conical convex surface having the same inclination angle as the conical concave surface. 3. The electric discharge machine according to claim 1, further comprising a guide member rotating means for rotating the guide member. 4. The electric discharge machining apparatus according to claim 1, further comprising electrode rotating means for rotating the electrode. 5. The electric discharge machining apparatus according to claim 1, further comprising: a guide member rotating unit that rotates the guide member; and an electrode rotating unit that rotates the electrode in a direction opposite to the guide member. . 6. An electric discharge machining method using the electric discharge machine according to claim 1 or 2, wherein the guide member is rotated during electric discharge machining. 7. An electric discharge machining method using the electric discharge machine according to claim 1 or 2, wherein the electrode is rotated during electric discharge machining. 8. The electric discharge machining method according to claim 6, wherein the electrode is rotated during the electric discharge machining. 9. The electric discharge machining method according to claim 8, wherein the electrode is rotated in a direction opposite to the guide member during the electric discharge machining. 10. The rotation speed of the guide member is feedback-controlled while detecting the discharge voltage generated between the member to be processed and the electrode while the guide member is being rotated, and the rotation speed of the member to be processed and the electrode are controlled. 10. The electric discharge machining method according to claim 6, wherein a gap formed in the rotational direction is adjusted.